The de-ionized water

used as the working fluid

flowed through the channel fitted with staggered array of micro pin-fins in circular

diamond

and ellipse shapes and the resistance characteristics were investigated experimentally. The investigation shows that the pressure drop increases with the flux with these three micro pin-fin groups. When the flux is very small

ellipse and diamond shape micro pin-fin groups present almost the same pressure drop because the influences of the shape of micro pin-fin on the flow is weakened by the laminar boundary layer

while the flow resistance of circular pin fins is maximal due to the longer flow distance. The pressure drop of the ellipse shape micro pin-fin is minimal compared with other two shapes of pin fins when the Reynolds number is relatively large. At low Re

the friction factor of diamond shape micro pin-fins with the same major axis and minor axis as the ellipse shape micro pin-fins is slightly smaller than that of ellipse shape pin-fin. The study also shows that the calculation values from the correlation related to the diamond shape micro pin-fins agree with experimental data among the three shapes of micro pin-fins.